The Myth of the ‘Healthy’ Obese

I was recently watching the stand-up comedy of John Pinette. For those of you who don’t know of him, he’s mostly famous for his comedy related to his obesity. In his recent performance he described how he went to the doctor for a checkup and got a “clean bill of health” based on his bloodwork and other tests.

The humor resided in the shock of his doctor trying to reconcile his enormity with his normality. This raises a common public misconception. For this reason, I think it’s important to debunk the myth that it’s possible to be obese and still have low risk for cardiovascular and other diseases if your cholesterol, blood pressure, and other risk factors are within the normal range.

The data supporting this was recently reported in the Annals of Internal Medicine this month. You can see the summary by clicking here. They pooled the data from eight studies that included over 60,000 patients. They then separated out all the obese (BMI ≥ 30) patients who did not have any measured risk factors for severe heart or vascular disease and called them ‘metabolically healthy’. These patients did NOT have:

waist circumference > 88cm (around 34.5 inches)

fasting triglycerides > 150 mg/dL

HDL cholesteral < 50 mg/dL

Systolic blood pressure (the top number) > 130

Diastolic blood pressure (the bottom number) > 85

The need for any blood pressure medications

Fasting blood sugar > 110 mg/dL

In other words these were obese patients who did not have high blood pressure, high cholesterol, diabetes, or a big belly. They had no risk factors for heart disease aside from their weight. Many people who fall in this category feel that they are off the hook and otherwise healthy.

The results of the study showed that the subjects who were ‘metabolically healthy’ and obese had a 24% higher chance of having a major cardiac event or death over the ensuing 10 years. The metabolically unhealthy and obese group had an even higher risk. The bottom line is that there now is more evidence that being obese in and of itself is a risk factor for heart disease and early death.

So why is this? Why is it that my doctor can tell me that all my tests are normal and my risk is still elevated?

The answer lies in the inherent imperfection of the tests that we in the medical community perform to predict risk. We are doctors and not prophets. All of our tests have a margin of error. As an example, I just saw a patient in the hospital that had a massive heart attack. One week prior he had a normal stress test. He was a bit perplexed. If his stress test was normal, how could he have had a heart attack. I explained that due to a combination of the nature of heart disease and the unavoidable imperfection of the test, a negative stress test is only 85% likely to be true. In other words, if you have a negative stress test, you still have a 15% chance of having a heart attack. The same is true (with different percentages) if you have normal blood pressure, cholesterol, waist circumference, and blood sugar. Of course, you’re much better off if these numbers are normal than abnormal, but this is not a guarantee of perfect health.

The bottom line is that medicine is an imperfect science. We know a whole lot, but not everything. The best you’ll ever be able to do is follow your doctor’s recommendations, eat right, exercise, and hope for the best. For the religious among you, the rest is up to the Lord. For the atheists, you’re stuck a victim of chance.

For some of you this will increase your anxiety as any lack of control will often do. But be careful, anxiety increases your risk of heart disease as well. It’s best to just let go, do your best, and enjoy the life you have. Happy holidays!